Forecasting time of condition of tide is important for anyone whose life touches and concerns the ocean, including those who navigate boats, particularly in coastal tidal areas, those who engage in fisheries including shell fish such as clams and scallops which are harvested at conditions of tide other than high tide, which activity is tide dependent, and those who engage in recreational activities along the seashore. Determining the time of a given tide, be it high or low or intermediate, is relatively easy on a current or day to day basis as tide information is published in a local newspaper, is often carried on the radio, and included on certain calendars. Furthermore, daily tide information is available through the use of well known, conventional "tide clocks" which are mechanically linked to a timing or clock mechanism, which indicate the time of high tide on a daily basis. However, forecasting time of high tide throughout a current month or future months is clearly more difficult task. Typically such forecasting involves the use of tide tables in conjunction with calendars, which often are expensive, cumbersome and typically are not readily available and convenient when making or changing plans which involve tidal waters.
Prior Art tide devices, in particular, tide clock devices, such as U.S. Pat. Nos. 4,848,949 issued 1989, 4,035,617 issued 1977, and 4,623,259 issued 1986 shows use of a display apparatus integrated with a clock mechanism to operate a tide indicating means to show the time of tide on a current daily basis. Another prior tide device is disclosed in U.S. Pat. No. 3,745,313 issued 1973 shows a board with a first scale having index marks signifying days of the year and a second scale having successive sections and index marks indicating the hours of the day. These tide clocks are complex and costly and do not provide a basis for quickly calculating a selected time of condition of tide in future months up to and including a period of twelve months in a simple tide disk.
However, in search of a simple device for fore-casting tides and through analysis of historical tidal records, I determined that the time of next high, or low, or "somewhere in between" tide can be determined by spacing the days date a certain angular distance on a circular display. The time of day, particularly the hour could be compared with this spacing of dates by using a disk display comparable adaptable to be in registration with the face of a conventional clock.
Accordingly it is therefore desirable to provide a simple, quick, convenient, non mechanical, and economical tide disk apparatus and method of calculating a selected condition of tide employing the tide disk which overcomes the disadvantages of the prior art.